Hi! Good evening. I am Dr Shareef answering your query. With a history of diverticulosis and the present abdominal pain with nausea and vomiting, I would presume it to be an attack of diverticulitis (bacterial infection of the diverticula) and start a bland diet regimen, a broad spectrum antibiotic along with an anearobic coverage, an anti inflammatory and a proton pump inhibitor with a probiotic. This might take a few days for your symptoms to improve, and a close watch on the symptoms with physical findings on examination of the abdomen would be required. In case there was no relief or if the symptoms increase in intensity, I would advise you to report to an ER of the nearest hospital for a possible admission and putting you on nil orally, and IV antibiotics and other related drugs. Further management would depend on the type of response obtained on the above regimen. I hope this information would help you in discussing with your family physician/treating doctor in further management of your problem. Please do not hesitate to ask in case of any further doubts. Thanks for choosing health care magic to clear doubts on your health problems. I wish you an early recovery. Dr Shareef.